Gunners striker Sanchez suffered a calf problem while in training with Chile and will sit out their first game with Colombia.
Sanchez’s injury will be assessed and depending on the result they may allow him to fly back to London before their game with Uruguay next Tuesday.
Chile FA officials insist the injury is not serious and they believe he has a chance to play in the second game.
Arsenal have been in touch and would be reluctant to take any chances.
They are hoping he will be OK to face Manchester United on Saturday week.
But Sanchez himself is keen on playing in the crucial qualifier against Uruguay next week.
Sanchez told El Mercurio: “It is hurting a bit but I’m fine. I’ll be back for Tuesday.”